Guidance on Emissions to Atmosphere
This Guidance Note was issued in 2004 to advise members of the University on the
environmental aspects of emissions to the atmosphere.
Contents
1.0 Introduction
2.0 Pollutants
3.0 Legislation
4.0 Sources of pollution
5.0 Pollution control
1.0 INTRODUCTION
1.1 The purpose of this guide is to characterise the most prolific pollutants emitted to
the atmosphere by the University, their sources and their potential effects upon
individuals and the environment. Means of reducing the quantity of emissions
released to the atmosphere by the University and current legislation (which must be
complied with in order to avoid the risk of prosecution) are also considered.
2.0 POLLUTANTS
2.1 Volatile Organic Compounds (VOCs). Volatile organic compounds are
compounds that have a high vapour pressure and low water solubility. Many VOCs
are man-made chemicals that are used and produced in the manufacture of paints,
pharmaceuticals, and refrigerants. VOCs typically are industrial solvents, such as
trichloroethylene; fuel oxygenates, such as methyl tert-butyl ether (MTBE) or byproducts produced by chlorination in water treatment, such as chloroform. VOCs are
often components of petroleum fuels, hydraulic fluids, paint thinners, and dry
cleaning agents. Therefore, during the course of many industrial processes, VOCs
are released to the atmosphere. Once released, they undergo a series of complex
reactions resulting in the formation of ground-level ozone, which is harmful to human
health and the environment. Some VOCs are quite harmful, including benzene,
polycyclic aromatic hydrocarbons (PAHs) and 1,3-butadiene. Benzene may increase
susceptibility to leukaemia, if exposure is maintained over a period of time, and PAHs
may be carcinogenic.
2.2 Chlorofluorocarbons (CFCs). CFCs, which may be found in existing
refrigeration and air-conditioning systems and halons, which may be found in firefighting systems, are commonly known as Ozone Depleting Substances (ODS). The
depletion of the ozone layer, which prevents harmful solar (UV-B) radiation reaching
the Earth's surface, has been caused by the use of these CFC gases. The danger to
humans from UV-B radiation includes damage to the eyes; damage to the immune
system and over time can lead to development of skin cancers.
2.3 Greenhouse gases. The atmospheric accumulation of certain gases (the
greenhouse gases), produced primarily from burning fossil fuels to generate power,
are changing the Earth’s energy balance so that global warming occurs, which may
lead to other effects such as a global rise in sea levels. Evidence indicates that in the
future, instances of heat related summer deaths may increase and there may also be
an increase in fatalities by major disasters caused by gales and coastal flooding. The
chief gas contributing to this effect is carbon dioxide, as well as methane, nitrous
oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur
hexafluoride.
2.4 Particulate matter (PM10). Particles with a diameter of 10 microns (PM10) are
the most hazardous of fine particles that can damage human health (dependent on
the chemical composition of the particulates), even at concentrations previously
thought to be unimportant. PM10 are composed of a wide range of materials from a
variety of sources, including:
 Primary particles arising from combustion processes
 Secondary particles, mainly sulphate and nitrate formed by chemical
reactions in the atmosphere
 Coarse particles composing of suspended soils and dusts, sea salt,
biological particles and particles from construction work
PM10 is among the most harmful of all air pollutants. When inhaled these particles
evade the respiratory system's natural defences and lodge deep in the lungs.
Health problems begin as the body reacts to these foreign particles. PM10 can
increase the number and severity of asthma attacks, cause or aggravate bronchitis
and other lung diseases, and reduce the body's ability to fight infections. Although
particulate matter can cause health problems for everyone, children, the elderly,
exercising adults, and those suffering from asthma or bronchitis are especially
vulnerable to PM10's adverse health effects. Also, recent studies have linked PM10
exposure to the premature death of people who already have heart and lung disease,
especially the elderly.
2.5 Lead. In the mid-1980s, the main source of lead emissions was identified as
traffic, as a result of which, the lead content of petrol is now controlled by legislation.
However, although this has vastly reduced the lead concentration in the air, lead still
affects air quality in urban areas and along heavily travelled motorways. The effects
of lead poisoning may be displayed as chronic effects on the nervous system
(especially in children), acute abdominal pain, kidney damage, high blood pressure
and many others.
2.6 Sulphur dioxide. Sulphur dioxide is emitted to the atmosphere when fossil fuels
are burnt primarily to generate power. It reacts with the water vapour already present,
so that precipitation has enhanced acidity. This results in the acidification of receiving
waters and consequent damage to ecosystems, especially lakes and forests. Acid
rain also accelerates the weathering of building materials. Effects on humans indicate
that exposure for asthmatics is significantly more damaging than for other people and
premature death through heart disease and bronchitis has been known to occur as a
result of severe exposure to sulphur dioxide.
2.7 Ground level ozone. Ozone is a secondary pollutant, not directly emitted from
manmade sources in any significant quantities. It is formed in the lower atmosphere
by the sunlight-initiated oxidation of VOCs in the presence of nitrogen oxides. Ozone
measured at a particular location may be the result of a reaction that took place
hundreds of kilometres away in the recent past. Evidence suggests that not only
does it affect people with impaired respiratory systems, but healthy adults and
children as well, and at fairly low concentrations.
Ozone is the prime ingredient of smog in cities and other areas of the country. It
interferes with the ability of plants to produce and store food, so that growth,
reproduction and overall plant health are compromised.
2.8 Carbon monoxide. Carbon monoxide is a product of incomplete burning of
hydrocarbon-based fuels and is emitted by vehicles. It primarily affects the air quality
in urban areas with heavy traffic. It inhibits the blood’s ability to carry oxygen to body
tissues, including vital organs such as the heart and brain, which may lead to
drowsiness or even asphyxiation at very high concentrations. It reacts with other
pollutants to produce ground-level ozone.
2.9 Nitrogen oxides. Nitrogen oxides (NOx) is a collective term used to refer to nitric
oxide (NO) and nitrogen dioxide (NO2). Nitrogen oxides are produced from
combustion processes from nitrogen in the air and to a lesser extent from nitrogen in
fuels. Nitric oxide is rapidly converted to nitrogen dioxide in the air by reaction with
ozone and other oxidants. The main source of emissions in the UK is road traffic.
Both nitric oxide and nitrogen dioxide are toxic. Nitrogen dioxide can irritate the lungs
and lower resistance to respiratory infections such as influenza. Continued or
frequent exposure to concentrations that are typically much higher than those
normally found in the atmosphere may cause increased incidence of acute
respiratory illness in children.
3.0 LEGISLATION
3.1 Integrated Pollution Prevention and Control (IPPC). In October 1996, the
European Commission published a Directive on Integrated Pollution Prevention and
Control (IPPC). This was introduced into England and Wales by the Pollution
Prevention and Control (PPC) Regulations 2000. All sites with listed activities have
until 2007 to comply with this legislation.
The IPPC Directive is designed to prevent, reduce and eliminate pollution (of all
natures) at source through the efficient use of natural resources. It is intended to help
operators of such premises to move towards greater environmental sustainability.
It will replace the current UK system of Integrated Pollution and Control (IPC),
and contains three parts:
 Part A(1) - This is a permitting system regulating emissions to the air, land
and water of potentially more polluting processes. The Environment Agency is
the regulator.
 Part A(2) - This is a permitting system regulating emissions to the air, land
and water of processes with a lesser potential to pollute. The Local Authority
is the regulator.
 Part B - This regime covers processes with a lesser potential to pollute. Only
emissions to the air are regulated. The Local Authority is the regulator.
Parts A(1) and A(2) will replace the IPC regime of Part 1 of the Environmental
Protection Act 1990 and will apply to a wider range of industries. These industries
include all installations that are currently regulated under IPC, some installations
currently regulated under Local Air Pollution Control (LAPC), and some installations
that are not currently under either regime such as landfill sites, intensive agriculture,
large pig and poultry units, and food and drink manufacturers. Parts A(1) and A(2)
aim to achieve a higher level of environmental protection as a whole and take into
account other factors, not covered by IPC, such as waste avoidance or minimisation,
energy efficiency, accident avoidance and minimisation of noise, heat and vibrations.
Part A(2) may sometimes be referred to as LA-IPPC.
Part B is also known as Local Air Pollution Prevention and Control (LAPPC) and this
will replace the older LAPC regime.
It requires operators of relevant installations to apply for authorisation permits, if they
do not already hold them, to continue legally operating. Currently, however, there are
no known processes within the University which require authorisation to comply with
this legislation. Yet, there is a requirement for individuals to be aware of it should
there be a change in systems of work in the future.
3.2 The Environment Act 1995. The Environment Act 1995 introduced the
requirement to establish the National Air Quality Strategy (NAQS), which set new Air
Quality Objectives (AQOs), to be met by 2005, for each of the following pollutants:
Table 1: Air Quality Objectives
Pollutant
Standard
Objective for 2005
Benzene
5ppb running annual mean
5ppb running annual mean
1,3-butadiene
1ppb running annual mean
1ppb running annual mean
Carbon monoxide
10ppm running 8 hour mean
10ppm running 8 hour mean
Lead
0.5µg/m3 annual mean
0.5µg/m3 annual mean
Nitrogen dioxide
150ppb - one hour mean
21ppb - annual mean
50µg/m3 running 24 hour mean
150ppb - one hour mean
21ppb - annual mean
50µg/m3 running 24 hour mean
(measured as 99th percentile)
100ppb - 15 minute mean
(measured as 99.9th percentile)
50ppb running 8 hour mean
(measured as 97th percentile)
PM10 (particulate
matter)
Sulphur dioxide
Ozone
100ppb - 15 minute mean
50ppb running 8 hour mean
Under the provisions of the Act, local authorities have the duty to review the air
quality in their areas where AQOs are being breached or are at risk of being
breached. They may do this by designating (Local) Air Quality Management Areas
(AQMAs) to remedy any problems. Currently, Cambridge City does not fall into this
category.
3.3 The Solvents Emissions Directive (SED). Solvents are regulated by EU
Council Directive 1999/13/EC, the Solvents Emissions Directive, which was enacted
into Pt 1 of the Environmental Protection Act 1990 and the Pollution Prevention and
Control Regulations 2000 in March 2002. This Directive sets Emission Limit Values
(ELVs) for VOCs from the use of organic solvents, and its purpose is:


To reduce air pollution by reducing releases of volatile organic compounds to
the environment;
To require safer substitutes for solvents known to be carcinogens, mutagens,
or toxic. It is also a prerequisite of the COSHH regulations to substitute
wherever reasonably practicable.
Generally, processes or sites that operate above the solvent consumption threshold
will need to either:
 Meet an ELV in waste gases and a fugitive emission limit value; or
 Meet the total ELV; or
 Implement a solvent reduction scheme to reduce emissions from the
installation equal to those that would be achieved by meeting the total
emission limit value.
However, there are stricter requirements for those activities using potentially more
harmful substances such as halogenated VOCs, or VOCs that are classified as
carcinogenic, mutagenic or toxic to reproduction.
3.4 Regulation on Ozone Depleting Substances. A new EU regulation which came
into force on 01 Oct 2000, Regulation on Ozone Depleting Substances 2037/2000,
banned production and use of the substances, and aids to speed up their removal.
Controlled substances for supply and use bans are CFCs, carbon tetrachloride,
1,1,1-trichlorethane, halons, hydrobromofluorocarbons and other fully halogenated
chlorofluorocarbons.
3.5 The Kyoto Protocol. Under the Kyoto Protocol, the UK has a legally binding
target to reduce emissions of the six major greenhouse gases by 12.5%, relative to
1990 levels over the period 2008 – 2012. It has also set a domestic goal to cut
carbon dioxide emissions by 20% below 1990 levels by 2010.
3.6 The Clean Air Act 1993. The Clean Air Act 1993 allowed Councils to establish
Smoke Control Areas to improve air quality by the burning of cleaner fuels in these
areas by controlling domestic and industrial smoke. These help the UK to meet air
quality standards for sulphur dioxide and particulates set by European law. Under the
Environmental Protection Act 1990 smoke emitted from a domestic chimney outside
a smoke control area is also covered by nuisance provisions.
3.7 Part III Environmental Protection Act 1990 (EPA 90). EPA 90 as amended by
the Noise and Statutory Nuisance Act 1993, contains the main legislation on statutory
nuisance and allows for action to be taken by either local authorities or individuals.
The following are deemed to be statutory nuisances when prejudicial to health, if they
become a nuisance or if they interfere with a persons’ legitimate use of land such as
neighbours in their homes and gardens:



Smoke emitted from premises
Fumes or gases from private dwellings
Dust, steam, smell or other effluvia from industrial, trade or business
premises
4.0 SOURCES OF EMISSIONS
4.1 Bonfires. Existing legislation does not prohibit bonfires in the UK. However,
under certain circumstances, smoke from a bonfire can be considered a statutory
nuisance and dealt with under the Environmental Protection Act (EPA)1990. The
smoke would have to be sufficient enough to warrant the closing of windows, and the
bonfires would have to be a regular occurrence for it to be considered a problem.
Although there are numerous Smokeless Control Areas throughout Cambridge,
which are areas where only smokeless fuel can be burnt, the Clean Air Act 1993
does not cover bonfires. Additionally, there may be products or substances in the
bonfire which remain unchanged in the ash and may cause contamination of the
ground on which the ash lies i.e. wood coated with lead based paint. Alternative
means of waste disposal should be considered before planning a bonfire, but should
it be deemed to be the ultimate solution, Cambridge City Council should be contacted
for advice (tel: 01223 457880) prior to lighting the bonfire.
4.2 Boiler houses. The Clean Air Act 1993 allowed the Council to establish Smoke
Control Areas to improve air quality by the burning of cleaner fuels in these areas (for
further details see: http://www.cambridge.gov.uk/env/burning%20issues.htm).
The Clean Air Act 1993 controls domestic and industrial smoke, and in doing so it
helps the UK to meet air quality standards for sulphur dioxide and particulates set by
European law. Accordingly, it is an offence to burn fuels which release dark smoke
into the atmosphere. For further information see:
http://www.hmso.gov.uk/acts/acts1993/Ukpga_19930011_en_1.htm.
4.3 Fume cupboards. A fume cupboard is a type of Local Exhaust Ventilation (LEV),
designed to protect individuals from exposure to chemical fumes, gases and
chemical aerosols. In the event of a requirement to install a new fume cupboard,
guidance should be sought from the Design Guide and Consultants Brief for
University Services and Construction Works, published by EM.
The vapours produced by the activities within the ducted fume cupboards are
extracted and diluted before being discharged to the atmosphere. This minimises the
exposure of airborne contaminants, but misuse or faulty units will drastically reduce
the effectiveness of a fume cupboard. They are not to be used as disposal routes for
toxic, noxious or flammable waste gases or vapours.
To ensure compliance with EPA 90, all users have a legal requirement to use the
best practicable means for preventing the emission into the atmosphere of noxious or
offensive substances, and for rendering harmless and inoffensive any substances
emitted.
Where possible, noxious emissions should be removed during the course of the
experiment by processes such as scrubbing or chemical absorption.
Prior to using a fume cupboard for the first time, all personnel should seek guidance
from the University Chemical Safety Adviser.
4.4 LEV (other than fume cupboards). The main function of a LEV system is to
reduce the concentration of hazardous fumes, dusts and vapours in the working
atmosphere to a level where they do not present a risk to the health of workers.
Examples of LEV other than fume cupboards include dust collectors, biological safety
cabinets, welding hoods, canopy hoods, bench hoods and downdraft hoods. In order
to be effective, a LEV system must be well designed and constructed, properly used
and maintained in good condition. Performance and efficiency can be impaired by
blockages and/or leaks in the ductwork or by the build up of contaminants.
Simple but important points in working with a local exhaust ventilation system
include:
 Do not put yourself between the source and the exhaust hood, as then you will
breathe in contaminants as they are drawn into the hood.
 Do not block the fresh air supply to the workplace.
 Do not block or obstruct the opening of the exhaust hood.
 Protect ventilation ducts from damage and holes.
 Where practicable, work close to the exhaust hood to improve capture of vapours
and fumes.
 Be aware of special precautions required when ventilating potentially explosive or
corrosive vapours.
 Prevent recirculation of exhaust air back into the workplace.
 Arrange for the inspection of the ventilation system every 14 months to ensure it
is operating as designed, and to comply with legislation.
4.5 Construction sites. There is the potential for construction sites to produce
substantial quantities of particulate matter, i.e. dust, during all phases of the
development. Project managers should be aware of this, especially during hot and
dry weather spells, and should ensure that dust levels are regularly monitored
throughout the working day, as it is difficult to suppress particulate matter when it
becomes airborne. It will be necessary to demonstrate that both nuisance dust and
fine particle emissions from construction sites are adequately controlled and are
within acceptable limits, in order to avoid prosecution under Part III of the
Environmental Protection Act 1990 or the IPPC regime.
4.6 Fugitive emissions. A fugitive emission is an emission of any chemical or
mixture of chemicals (in any physical form), which is not expelled via a stack or other
means of extraction. They may occur as a result of an accident and are relatively
infrequent. Other fugitive emissions may be due to leaking equipment, i.e. valves and
pumps, or be a result of incomplete solvent capture, i.e. when filling containers. They
are extremely difficult to identify as they often involve leaks to the atmosphere, and
due to the nature of organic solvent, any visual liquid leak will rapidly evaporate.
Benefits of reducing fugitive emissions include: Reduced solvent consumption.
 Reduced maintenance costs.
 Better working conditions.
 Fewer odours.
 Improved environmental performance and image.
4.7 Vehicle emissions. In the last number of years, there has been a significant
increase in the number of vehicles on the roads in Cambridge. Altogether, the
University has a large vehicle fleet consisting of an assortment of type and make.
These all help to contribute towards the emission of carbon monoxide and other
pollutants to the atmosphere. All University staff and students should be aware that
the University actively promotes a park and cycle ethos where reasonably
practicable.
5.0 EMISSIONS CONTROL
5.1 It is the duty of all staff and students to ensure that where possible, they take
positive action to reduce the amount of harmful emissions to the atmosphere and that
they do not breach any relevant legislation. The options for pollution control can be
broken down into three categories and are listed below:
Management controls
 Ensure procedural controls are in place i.e. works instructions, regular
maintenance and inspection of equipment.
 Ensure all staff and students receive the relevant training, including
refresher training.
 Ensure compliance with all procedures and legislation.
 Initiate emergency procedures in case of spillages or systems failures.
 Embark upon a regular monitoring programme to certify that systems are
functioning correctly and that there aren’t any fugitive emissions. For
further advice, contact the Environmental Office.
 Periodically review procedures and amend as required.


Implement an energy plan in an attempt to reduce the quantity of energy
used.
Encourage the utilisation of bicycles to limit vehicle use.
Advanced practical controls
 Replace the process with clean technology i.e. paint dipping as opposed
to paint spraying.
 Use closed loop systems where possible, such as solvent recovery.
 Where possible, employ engineering controls such as air filtration, water
treatment or containment to minimise the quantity of pollution.
 Use energy supplied from ‘green’ sources.
 Use alternative fuels.
 Install a combined heating and power (CHP) plant.
 Change processes to avoid the formation of mists, i.e. dip coating instead
of spray painting.
 Replace existing vehicles with improved energy efficient models, or those
powered by alternative fuels.
 Improve combustion conditions to maximise energy output and reduce
emissions.
Practical controls
 Examine the process, and where possible eliminate the material or
process.
 Examine the process, and where possible substitute the material with
something less harmful.
 Reduce the quantities of harmful materials used.
 Keep containers of VOCs tightly closed when not in use. Preferably, use a
material that does not use solvent-based VOCs.
 Segregated work areas to minimise the spread of dust.
 Where practicable, on construction sites, water should be sprayed onto
areas of the site that may give rise to dust clouds.
 Ensure that any wagon or skip that leaves a construction site fully laden
with construction waste is covered with a tarpaulin.